Replenishment system for a processing device



I United States Patent Wallace L. Pensgen Rochester, New York Oct. 20,1967 Oct. 6, 1970 Eastman Kodak Company Rochester, New York acorporation of New Jersey [72] Inventor App]. No. Filed PatentedAssignee REPLENISHMENT SYSTEM FOR A PROCESSING DEVICE 7 Claims, 2Drawing Figs.

U.S.Cl 95/89 lnt.Cl G03d 3/06 Field otSearch 95/89(i\iise). 89(Lam).94:1 18/18; 68/(lnquired):

l37/(lnquired): ZZZ/(inquired) PUMP [56] References Cited UNITED STATESPATENTS 2,773,734 1 1957 Fairbank 95/94 3,143,056 3/1964 Llmberger 95 93,146,]26 8/1964 Barker 113 2 3,334,566 8/l967 i-riedel 95 PrimaryExaminer-Norton Ansher Assistant Examiner-Fred L. Braun Atlorneys-Robert W. Hampton and Steve W. Gremban ABSTRACT: A replenishment systemfor replenishing a substance such as a solution in a processing devicesuch as a photographic processing device in which the rate of substancereplenishment is controlled by a sensing mechanism. The sensingmechanism senses the sheet or web material and produces a fluid pressureoutput that is responsive to the width of the material being processed.The output produced, in turn, actuates a device for controlling the rateof substance replenishment.

44 PROCESSING SOLUTION SUPPLY FILM DRIVE MOTOR CONTROL PROCESSINGSOLUTION CHAMBER Patented Oct. 6, 1970 o (D c ATTORNEYS REPLENISHMENTSYSTEM FOR APROCESSING DEVICE BACKGROUND OF THE INVENTION This inventionrelates generally to processors, and more specifically to an improvedprocessing device having a substance replenishment system and means forproducing an output proportional to the width of a material transportedthrough the processor. Control means are actuated in response to theoutput for controlling the substance replenishment system.

In photographic processing operations that do not utilize throwawayprocessing solutions, it is difficult to maintain the concentration ofthe various processing solutions at proper strength. This isparticularly a problem with developer solutions which during processingreduce light exposed grains of silver halide in the film emulsion tometallic silver. This chemical reduction or development process must becarefully controlled with respect to a number of variables. In the usualpractice, the initial exposure is controlled so as to give a latentimage which, when processed under standard conditions, will develop tothe proper density. Obviously, if the conditions are other thanstandard, the image will be either over or underdeveloped, and the imagequality correspondingly poor. The most important variables in theprocessing operation are time, temperature and the concentration of thesolution. The time of development is easily controlled by a variety ofwell known mechanical means, or may be controlled manually by theoperator with the aid of a timer. Similarly, control of the processingtemperature ordinarily presents no particular difficulty. The remainingvariable, namely control of the concentration of the processingsolution, however, is more of a problem. Beingreducing agents, thesolutions are subject to oxidation by the atmosphere, and such oxidationconsumes the reducing agents, lowering the effective concentration ofthe solutions. Also, each portion of photographic material (film, paper,etc.) that is processed consumes a portion of the reducing agents in theprocessing solutions so that the solu tions gradually become exhausted.

The traditional approach to the problem of keeping the processingsolution strength constant within reasonable limits has been to uselarge volumes of solution, protecting them so far as possible againstatmospheric oxidation, and to limit the square footage of film processedby a given quantity of solution so that the effective concentration ofthe solution does not vary appreciably between the first and the lastportions of film processed. This approach, however, is wasteful since ifthe concentration of the solution when discarded is substantially thesame as its concentration when fresh, large quantities of relativelyunused processing solution are necessarily discarded. Applicant'sinvention involves a different approach in which the processing devicecontains a predetermined quantity of processing solution, and freshprocessing solution is automatically added to the original solution asit is depleted during the processing operation to build up and maintainthe strength of the solution at a relatively constant value.

It is, of course, generally well known in the art to provide mechanismssuch as motion picture projectors and tape recorders capable ofdetecting the presence or absence of a web, and in response thereto toactuate web reversing mechanisms. It is also known in the art to providea processing solution replenishment system in which a test strip of filmas it is being processed is subjected to a light-sensing device whichgives an electrical indication of the degree of processing, and hencethe strength of the processing solution, and produces an outputproportional to such indication for controlling the rate of solutionreplenishment/However, applicant is unaware of any substancereplenishment system such as a processing solution replenishment systemfor a processing device for controlling the rate of substancereplenishment by a pressure output produced by a material sensingmechanism that is responsive to the width of the material, such outputin turn actuating means for controlling the rate of substancereplenishment.

SUMMARY OF THE INVENTION This invention includes within its scope asubstance replenishment system such as a processing solutionreplenishment system for a processing device such as a photographicprocessing device. A material sensing mechanism in the processing deviceis responsive to the width of the material in sheet or web form as it istransported through the processing device for producing a pressureoutput. The pressure output is produced by a pressure system such as anegative pressure system in which the amount of negative pressuregenerated is proportional to the width of the material and increases asthe width of the material increases. This pressure output actuatescontrol means for controlling the rate of substance replenishment.

One object of the present invention is to provide a processing substancereplenishment system for a processing device having a material sensingmechanism that is responsive to the width of the material as it istransported through the processing device for producing a pressureoutput, such output in turn actuating control means for controlling therate of substance replenishment.

Objects and advantages other than those set forth above will be apparentfrom the following description when read in connection with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWING In the drawing:

FIG. I is a schematic view of a processing apparatus such as aphotographic processing device showing the developing, fixing, washingand drying chambers thereof; and

FIG. 2 is a schematic view partially in perspective and partially inblock diagram form ofa processing solution replenishment system for aprocessing device, in which portions of the processing device have beenomitted for purposes of clarity.

DETAILED DESCRIPTION Referring to the drawing, this invention is shownschematically in connection with a processing device 10v of any knowntype such as a photographic processor having developing, fixing, washingand drying chambers l2, l4, l6 and 18 respectively. The processingdevice I0 has a pressure means for sensing sheet or web materialcomprising a feed table 20 over which the material such as a film 22 istransported. The film feed table 20 has a recess extending laterallythereof as shown dotted in FIG. 2 to form a chamber 24, and a pluralityof small spaced openings 26 extending from the top of table 20 intochamber 24. Although chamber 24 is shown integral with table 20, it maybe a separate unit secured to the table or to any other portion of theprocessing device 10 provided the film 22 to be processed is transportedover it. A conduit 28 has one end connected to the bottom of chamber 24,and the other end thereof connected to a pump 30 for drawing air throughopenings 26 and chamber 24. The conduit 28 is provided with a negativepressure or partial vacuum adjustment bleed valve 32 for controlling theamount of negative pressure generated or developed in conduit 28 andchamber 24.

The control means which is responsive to the pressure film sensingmechanism comprises a movable mechanism of any known type such as apiston 34 connected to conduit 28 and movable in a cylinder 36 by thenegative pressure generated in conduit 28 when the film covers one ormore of the openings 26 in chamber 24. The amount of negative pressuredeveloped is proportional to the number of openings covered, and hencethe width of the film, and becomes greater as more of the openings arecovered. The movement of piston 34 is proportional to the amount ofnegative pressure generated, and controls a valve 40 in a processingsolution supply conduit 42 by means of a rod 38 interconnecting piston34 and valve 40. A pump 44 pumps processing solution from any suitablesource or supply of processing solution through conduit 42 and valve 40to one of the processing solution chambers 12, 14 for replenishing same.A similar supply, pump and valve system,

now shown, preferably operated by rod 38 may be utilized to replenishthe remaining chamber. Naturally, as the width of the film beingprocessed increases, the negative pressure generated increases resultingin valve 40 being increasingly opened with a corresponding increasinglyhigher rate of solution replenishment. The replenishment continues aslong as film 22 covers the openings, and when the openings areuncovered, valve 40 is immediately returned by piston 34 to its normalpreset position for providing a standby rate of replenishment or forturning off the replenishment completely, depending upon how it isinitially set.

It should be readily apparent that other forms of movable mechanismsother than a piston system may be utilized in this invention such as atransducer responsive to the variable pressure generated to provide avariable electrical output connected to a variable speed motor driving asolution pump, the output of which is proportional to the speed at whichit is driven. A film transport motor control 46 of known type forprocessor has a potentiometer 48 for controlling the speed at which film22 is transported through the processor, normally by pairs of opposedrollers, and this motor control may be connected to valve 40 forautomatically adjusting the valve opening relative to piston 34 tocorrespond to the speed of film transport. The greater the speed of filmtransport, the greater the valve opening thereby increasing the solutionreplenishment rate to compensate for the shorter period of time piston34 is actuated and solution pump 44 is operated.

In the operation of this invention, when a material such as aphotographic film is introduced into the processing device 10 of a widthcapable of covering one or more openings 26 in chamber 24, the negativepressure generated in the system moves piston 34 and valve 40 to adjustthe solution replenishment rate in proportion to the width of the film.Solution replenishment will continue as long as film 22 covers Openings26. As soon as the openings are uncovered, valve 40 will return to itsnormal position causing the solution replenishment rate to return to itsnormal nominal rate for standby operation, or to be turned off entirelydepending on the preset position of valve 40.

The invention has been described in detail with particular reference toone embodiment thereof, but it will be understood that variations andmodifications can be effected within the spirit and scope of theinvention as described hereinabove.

lClaim: v

1. In a photographic processing device having a processing solutionreplenishment system, the combination comprising:

means containing a processing solution;

means for transporting a photographic film material through theprocessing device for processing;

means for replenishing solution to the containing means at a varyingrate to maintain the strength of the solution at a predetermined value;

fluid pressure means for sensing film transported through the processingdevice and producing a fluid pressure output proportional to the widthof the film that is processed; and

control means for said solution replenishing means responsive to thefluid pressure output of said film sensing fluid pressure means forcontrolling the rate of solution replenishment whereby the strength ofthe solution is maintained at said predetermined value.

2. The invention according to claim 1 wherein said pressure sensingmeans comprises a chamber having openings therein across which the filmis transported, and a pump connected to said chamber and to saidsolution replenishing means for producing a negative pressure outputproportional to the width of the film transported across said openings.

3. The invention according to claim 1 wherein said solution replenishingmeans comprises an adjustable valve, and said control means comprises apiston connected to said valve and responsive to the fluid pressureoutput of said pressure sensing means for controlling said valve and therate of solution replenishment.

4. The invention according to claim 1 wherein said fluid pressuresensing means comprises a chamber having openings therein across whichthe film is transported, and a pump connected to said chamber and tosaid solution replenishing means for producing a negative pressureoutput proportional to the width of the film transported across saidopenings; said solution replenishing means comprises an adjustable valvefor controlling the rate of solution replenishment; and said controlmeans comprises a piston connected to said valve and responsive to thepressure output of said pressure sensing means for adjusting said valveand the rate of solution replenishment.

5. In a processing solution replenishment system for a photographicprocessing device containing a processing solution through which anexposed photographic film material is transported for processing, thecombination comprising:

fluid pressure means for sensing a film transported through theprocessing device and producing a fluid pressure output proportional tothe width of the film that is processed;

means for replenishing the processing solution at a varying rate tomaintain the strength of the solution at a predetermined value; and

control means for said solution replenishing means and responsive tosaid fluid pressure film sensing and pressure output producing means forcontrolling the rate of solution replenishment.

6. The invention according to claim 5 wherein said film sensing andpressure output producing means comprises a chamber having openingstherein, said chamber being connected to said solution replenishingmeans, and a pump connected to said chamber for producing a negativepressure in said chamber when a film is transported across said openingscausing an increase in the rate of solution replenishment proportionateto the number of openings covered.

7. In a material handling device having substance containing means andmeans for transporting the material through the device and into contactwith the substance, the combination comprising:

means for replenishing the substance at a varying rate as it is used bythe material;

fluid pressure means for sensing material transported through the deviceand producing a fluid pressure output proportional to the width of thematerial; and

control means for said replenishing means responsive to the fluidpressure output of said material sensing pressure means for controllingthe rate of substance replenishment.

